[libc++] Add a CI job running MSAN
For some reason, we've been going without a MSAN CI job, even though
even run-buildbot defined a generic-msan job. This must have been an
oversight that went unnoticed. Thanks to @EricWF for the catch.
Differential Revision: https://reviews.llvm.org/D120851
NOKEYCHECK=True
GitOrigin-RevId: cb055e51f994806160465212ac100485dac48125
diff --git a/test/signal_frame.pass.cpp b/test/signal_frame.pass.cpp
index 85a883b..d9fb439 100644
--- a/test/signal_frame.pass.cpp
+++ b/test/signal_frame.pass.cpp
@@ -12,6 +12,9 @@
// TODO: Investigate this failure on macOS
// XFAIL: target={{.+}}-apple-darwin{{.+}}
+// TODO: Figure out why this fails with Memory Sanitizer.
+// XFAIL: msan
+
// UNSUPPORTED: libunwind-arm-ehabi
// The AIX assembler does not support CFI directives, which